Functional inactivation of menin, encoded by the MEN1 gene, causes the inherited multiple endocrine neoplasia type 1 (MEN1) syndrome and some but not all sporadic pancreatic endocrine tumors. Therefore, exploring molecular events upstream or downstream of menin could point to other causative genes and/or regulatory events responsible for such tumor types. Our current efforts are directed towards studying 2 categories of genes for menin-regulated transcriptional, post-transcriptional, protein:protein interaction, and sub-cellular localization events: 1) Cyclin-dependent kinases and their inhibitors, and 2) Endocrine pancreas differentiation factors.